init

whisper.cpp-1.5.2/examples/wchess/libwchess/CMakeLists.txt

@@ -0,0 +1,19 @@
+add_library(wchess-core STATIC
+    WChess.cpp
+    WChess.h
+    Chessboard.cpp
+    Chessboard.h
+)
+
+target_link_libraries(wchess-core
+    PUBLIC
+    whisper
+    common
+)
+
+target_include_directories(wchess-core
+    PUBLIC
+    "$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>"
+)
+
+# add_executable(test-chessboard test-chessboard.cpp Chessboard.cpp)

whisper.cpp-1.5.2/examples/wchess/libwchess/Chessboard.cpp

@@ -0,0 +1,803 @@
+#include "Chessboard.h"
+
+#include <array>
+#include <vector>
+#include <algorithm>
+#include <cstring>
+#include <set>
+#include <list>
+#include <chrono>
+
+namespace {
+constexpr std::array<const char*, 64> positions = {
+    "a1", "b1", "c1", "d1", "e1", "f1", "g1", "h1",
+    "a2", "b2", "c2", "d2", "e2", "f2", "g2", "h2",
+    "a3", "b3", "c3", "d3", "e3", "f3", "g3", "h3",
+    "a4", "b4", "c4", "d4", "e4", "f4", "g4", "h4",
+    "a5", "b5", "c5", "d5", "e5", "f5", "g5", "h5",
+    "a6", "b6", "c6", "d6", "e6", "f6", "g6", "h6",
+    "a7", "b7", "c7", "d7", "e7", "f7", "g7", "h7",
+    "a8", "b8", "c8", "d8", "e8", "f8", "g8", "h8",
+};
+constexpr char INVALID_POS = positions.size();
+constexpr int R = 0; // rank index
+constexpr int F = 1; // file index
+#define FILE (c[F] - '1')
+#define RANK (c[R] - 'a')
+constexpr char operator ""_P(const char * c, size_t size) {
+    return size < 2 || RANK < 0 || RANK > 7 ||
+        FILE < 0 || FILE > 7 ? INVALID_POS : FILE * 8 + RANK;
+}
+#undef FILE
+#undef RANK
+
+struct sview {
+    const char * ptr = nullptr;
+    size_t size = 0;
+
+    sview() = default;
+    sview(const char * p, size_t s) : ptr(p), size(s) {}
+    sview(const std::string& s) : ptr(s.data()), size(s.size()) {}
+
+    size_t find(char del, size_t pos) {
+        while (pos < size && ptr[pos] != del) ++pos;
+        return pos < size ? pos : std::string::npos;
+    }
+};
+
+std::vector<sview> split(sview str, char del) {
+    std::vector<sview> res;
+    size_t cur = 0;
+    size_t last = 0;
+    while (cur != std::string::npos) {
+        if (str.ptr[last] == ' ') {
+            ++last;
+            continue;
+        }
+        cur = str.find(del, last);
+        size_t len = cur == std::string::npos ? str.size - last : cur - last;
+        res.emplace_back(str.ptr + last, len);
+        last = cur + 1;
+    }
+    return res;
+}
+
+char strToPos(sview str) {
+    return operator ""_P(str.ptr, str.size);
+}
+
+constexpr std::array<const char*, 6> pieceNames =  {
+    "pawn", "knight", "bishop", "rook", "queen", "king",
+};
+
+static constexpr std::array<char, 6> blackShort =  {
+    'p', 'n', 'b', 'r', 'q', 'k',
+};
+static constexpr std::array<char, 6> whiteShort =  {
+    'P', 'N', 'B', 'R', 'Q', 'K',
+};
+
+char strToType(sview str) {
+    auto it = std::find_if(pieceNames.begin(), pieceNames.end(), [str] (const char* name) { return strncmp(name, str.ptr, str.size) == 0; });
+    return it != pieceNames.end() ? it - pieceNames.begin() : pieceNames.size();
+}
+
+// directions
+using Direction = std::array<char, 2>;
+
+constexpr Direction N   = {(char)  0, (char)  1};
+constexpr Direction NNE = {(char)  1, (char)  2};
+constexpr Direction NE  = {(char)  1, (char)  1};
+constexpr Direction ENE = {(char)  2, (char)  1};
+constexpr Direction E   = {(char)  1, (char)  0};
+constexpr Direction ESE = {(char)  2, (char) -1};
+constexpr Direction SE  = {(char)  1, (char) -1};
+constexpr Direction SSE = {(char)  1, (char) -2};
+constexpr Direction S   = {(char)  0, (char) -1};
+constexpr Direction SSW = {(char) -1, (char) -2};
+constexpr Direction SW  = {(char) -1, (char) -1};
+constexpr Direction WSW = {(char) -2, (char) -1};
+constexpr Direction W   = {(char) -1, (char)  0};
+constexpr Direction WNW = {(char) -2, (char)  1};
+constexpr Direction NW  = {(char) -1, (char)  1};
+constexpr Direction NNW = {(char) -1, (char)  2};
+
+char makeStep(char pos, const Direction& d) {
+    char next[2] = { char(positions[pos][R] + d[R]) , char(positions[pos][F] + d[F]) };
+    return strToPos(sview{next, sizeof(next)});
+}
+
+template<class Modifier>
+char traverse(char pos, const Direction& d, const Modifier& m, int count = 8) {
+    while (--count >= 0) {
+        pos = makeStep(pos, d);
+        if (pos == INVALID_POS || m(pos)) break;
+    }
+    return pos;
+}
+
+Direction normalize(const Direction& distance) {
+    //return {char((distance[R] > 0) - (distance[R] < 0)), char((distance[F] > 0) - (distance[F] < 0))};
+    const int drp = distance[R] > 0 ? 1 : 0;
+    const int drn = distance[R] < 0 ? 1 : 0;
+    const int dfp = distance[F] > 0 ? 1 : 0;
+    const int dfn = distance[F] < 0 ? 1 : 0;
+    return {char(drp - drn), char(dfp - dfn)};
+}
+
+struct Pin {
+    Direction d;
+    Piece* pinner;
+    Piece* pinned;
+};
+using Pins = std::list<Pin>;
+using Board = std::array<Piece*, 64>;
+
+std::vector<Direction> filter(const Direction& pin, std::initializer_list<Direction> directions) {
+    if (pin[R] == 0 && pin[F] == 0) return directions;
+    std::vector<Direction> result;
+    for (auto& d : directions) {
+        if ((d[R] == pin[R] || d[R] == -pin[R]) && (d[F] == pin[F] || d[F] == -pin[F])) result.push_back(d);
+    }
+    return result;
+}
+}
+
+class Piece {
+public:
+    enum Types : char {
+        Pawn,
+        Knight,
+        Bishop,
+        Rook,
+        Queen,
+        King,
+        //
+        NUM_PIECES
+    };
+
+    enum Colors : char {
+        White,
+        Black,
+    };
+
+    const char* name() const;
+    char initial() const;
+    Types type() const { return m_type; }
+    Colors color() const { return m_color; }
+    char pos() const { return m_pos; }
+    void setPos(char pos) {
+        m_pos = pos;
+        invalidate();
+    }
+    const char* coord() const;
+    const std::set<char>& allowed() const { return m_allowed; }
+    bool canReach(char pos) const;
+    virtual bool movePattern(char pos) const = 0;
+    void take();
+    virtual void reinit(const State& state) = 0;
+    void invalidate();
+protected:
+    Piece(Types type, Colors color, char pos, std::set<char> allowed)
+        : m_type(type), m_color(color), m_pos(pos), m_allowed(std::move(allowed)) {}
+    Piece(const Piece&) = delete;
+    ~Piece() = default;
+
+    const Types m_type;
+    const Colors m_color;
+    char m_pos;
+    std::set<char> m_allowed;
+    bool m_update = false;
+};
+
+struct Pawn : public Piece {
+    Pawn(Colors color, char pos, std::set<char> next) : Piece(Types::Pawn, color, pos, std::move(next)) {}
+
+    bool is_first_move() const {
+        return m_color ? coord()[F] == '7' : coord()[F] == '2';
+    }
+
+    virtual bool movePattern(char pos) const override {
+        if (m_pos == INVALID_POS) return false;
+        auto cur = coord();
+        auto next = positions[pos];
+        Direction distance = {char(next[R] - cur[R]), char(next[F] - cur[F])};
+        char forward = m_color ? -1 : 1;
+        return (forward == distance[F] && distance[R] * distance[R] <= 1)
+            || (is_first_move() && 2 * forward == distance[F] && distance[R] == 0);
+    }
+
+    virtual void reinit(const State& state) override;
+};
+
+struct Knight : public Piece {
+    Knight(Colors color, char pos, std::set<char> next) : Piece(Types::Knight, color, pos, std::move(next)) {}
+
+    virtual bool movePattern(char pos) const override {
+        if (m_pos == INVALID_POS) return false;
+        auto cur = coord();
+        auto next = positions[pos];
+        Direction diff = {char(next[R] - cur[R]), char(next[F] - cur[F])};
+        return diff[R]*diff[R] + diff[F]*diff[F] == 5;
+    }
+
+    virtual void reinit(const State& state) override;
+};
+
+struct Bishop : public Piece {
+    Bishop(Colors color, char pos) : Piece(Types::Bishop, color, pos, {}) {}
+
+    virtual bool movePattern(char pos) const override {
+        if (m_pos == INVALID_POS) return false;
+        auto cur = coord();
+        auto next = positions[pos];
+        return cur[R] - cur[F] == next[R] - next[F] || cur[R] + cur[F] == next[R] + next[F];
+    }
+
+    virtual void reinit(const State& state) override;
+};
+
+struct Rook : public Piece {
+    Rook(Colors color, char pos) : Piece(Types::Rook, color, pos, {}) {}
+
+    virtual bool movePattern(char pos) const override {
+        if (m_pos == INVALID_POS) return false;
+        auto cur = coord();
+        auto next = positions[pos];
+        return cur[R] == next[R] || cur[F] == next[F];
+    }
+
+    virtual void reinit(const State& state) override;
+};
+
+struct Queen : public Piece {
+    Queen(Colors color, char pos) : Piece(Types::Queen, color, pos, {}) {}
+
+    virtual bool movePattern(char pos) const override {
+        if (m_pos == INVALID_POS) return false;
+        auto cur = coord();
+        auto next = positions[pos];
+        return cur[R] == next[R] || cur[F] == next[F] || cur[R] - cur[F] == next[R] - next[F] || cur[R] + cur[F] == next[R] + next[F];
+    }
+
+    virtual void reinit(const State& state) override;
+};
+
+struct King : public Piece {
+    King(Colors color, char pos) : Piece(Types::King, color, pos, {}) {}
+
+    virtual bool movePattern(char pos) const override {
+        if (m_pos == INVALID_POS) return false;
+        auto cur = coord();
+        auto next = positions[pos];
+        Direction diff = {char(next[R] - cur[R]), char(next[F] - cur[F])};
+        return diff[R]*diff[R] + diff[F]*diff[F] <= 2;
+    }
+
+    virtual void reinit(const State& state) override;
+};
+
+struct PieceSet {
+    Piece* begin() { return &p1; }
+    Piece* end() { return &r2 + 1; }
+    const Piece* begin() const { return &p1; }
+    const Piece* end() const { return &r2 + 1; }
+    Piece& operator[](int i) { return *(begin() + i); }
+    const Piece& operator[](int i) const { return *(begin() + i); }
+
+    Pawn   p1;
+    Pawn   p2;
+    Pawn   p3;
+    Pawn   p4;
+    Pawn   p5;
+    Pawn   p6;
+    Pawn   p7;
+    Pawn   p8;
+    Rook   r1;
+    Knight n1;
+    Bishop b1;
+    Queen  q;
+    King   k;
+    Bishop b2;
+    Knight n2;
+    Rook   r2;
+};
+
+struct State {
+    State();
+    PieceSet blacks;
+    PieceSet whites;
+    Board board;
+    Pins blackPins;
+    Pins whitePins;
+};
+
+Direction findPin(const Piece& piece, const State& state) {
+    auto& pins = piece.color() ? state.blackPins : state.whitePins;
+    auto it = std::find_if(pins.begin(), pins.end(), [&] (const Pin& pin) { return pin.pinned == &piece; });
+    if (it != pins.end()) return it->d;
+    return {0, 0};
+}
+
+struct Find {
+    Find(const Board& board) : m_board(board) {}
+    bool operator() (char pos) const { return m_board[pos]; }
+    const Board& m_board;
+};
+
+struct Add {
+    Add(const Board& board, std::set<char>& moves, Piece::Colors color) : m_board(board), m_moves(moves), m_color(color) {}
+    bool operator() (char pos) const {
+        if (!m_board[pos] || m_board[pos]->color() != m_color) m_moves.insert(pos);
+        return m_board[pos];
+    }
+    const Board& m_board;
+    std::set<char>& m_moves;
+    Piece::Colors m_color;
+};
+
+void Pawn::reinit(const State& state) {
+    if (m_pos == INVALID_POS) return;
+    if (!m_update) return;
+    m_update = false;
+    m_allowed.clear();
+
+    auto pin = findPin(*this, state);
+
+    auto & left = m_color ? SW : NW;
+    auto & right = m_color ? SE : NE;
+
+    for (auto& direction : filter(pin, { left, right })) {
+        auto pos = makeStep(m_pos, direction);
+        if (pos != INVALID_POS && state.board[pos] && state.board[pos]->color() != m_color) m_allowed.insert(pos);
+    }
+
+    auto & forward = m_color ? S : N;
+    if (!filter(pin, {forward}).empty()) {
+        traverse(m_pos, forward, [&] (char pos) {
+                if (!state.board[pos]) m_allowed.insert(pos);
+                return state.board[pos] || !is_first_move();
+            }, 2);
+    }
+}
+
+void Knight::reinit(const State& state) {
+    if (m_pos == INVALID_POS) return;
+    if (!m_update) return;
+    m_update = false;
+    m_allowed.clear();
+    auto pin = findPin(*this, state);
+    if (pin[R] != 0 || pin[F] != 0) return;
+    for (auto& direction : { NNE, ENE, ESE, SSE, SSW, WSW, WNW, NNW }) {
+        auto pos = makeStep(m_pos, direction);
+        if (pos != INVALID_POS && (!state.board[pos] || state.board[pos]->color() != m_color)) m_allowed.insert(pos);
+    }
+}
+
+void Bishop::reinit(const State& state) {
+    if (m_pos == INVALID_POS) return;
+    if (!m_update) return;
+    m_update = false;
+    m_allowed.clear();
+    auto pin = findPin(*this, state);
+    for (auto& direction : filter(pin, { NE, SE, SW, NW })) {
+        traverse(m_pos, direction, Add(state.board, m_allowed, m_color));
+    }
+}
+
+void Rook::reinit(const State& state) {
+    if (m_pos == INVALID_POS) return;
+    if (!m_update) return;
+    m_update = false;
+    m_allowed.clear();
+    auto pin = findPin(*this, state);
+    for (auto& direction : filter(pin, { N, E, S, W })) {
+        traverse(m_pos, direction, Add(state.board, m_allowed, m_color));
+    }
+}
+
+void Queen::reinit(const State& state) {
+    if (m_pos == INVALID_POS) return;
+    if (!m_update) return;
+    m_update = false;
+    m_allowed.clear();
+    auto pin = findPin(*this, state);
+    for (auto& direction : filter(pin, { N, NE, E, SE, S, SW, W, NW })) {
+        traverse(m_pos, direction, Add(state.board, m_allowed, m_color));
+    }
+}
+
+void King::reinit(const State& state) {
+    if (m_pos == INVALID_POS) return;
+    if (!m_update) return;
+    m_update = false;
+    m_allowed.clear();
+    auto& enemyPieces = m_color ? state.whites : state.blacks;
+    auto& pawnAttackLeft = m_color ? SW : NW;
+    auto& pawnAttackRight = m_color ? SE : NE;
+    for (auto& direction : { N, NE, E, SE, S, SW, W, NW }) {
+        auto pos = makeStep(m_pos, direction);
+        bool accept = pos != INVALID_POS && !(state.board[pos] && state.board[pos]->color() == m_color);
+        if (accept) {
+            for (auto& p : enemyPieces) {
+                if (!p.movePattern(pos)) continue;
+                if (p.type() == Piece::Knight || p.type() == Piece::King) {
+                    accept = false;
+                    break;
+                }
+                else if (p.type() == Piece::Pawn) {
+                    auto from = positions[pos];
+                    auto to = p.coord();
+                    Direction d {char(to[R] - from[R]), char(to[F] - from[F])};
+                    if (d == pawnAttackLeft || d == pawnAttackRight) {
+                        accept = false;
+                        break;
+                    }
+                }
+                else {
+                    auto from = positions[pos];
+                    auto to = p.coord();
+                    Direction d = normalize({char(to[R] - from[R]), char(to[F] - from[F])});
+                    auto reached = traverse(pos, d, Find(state.board));
+                    if (p.pos() == reached) {
+                        accept = false;
+                        break;
+                    }
+                }
+            }
+        }
+        if (accept) m_allowed.insert(pos);
+    }
+}
+
+const char* Piece::name() const {
+    static_assert(pieceNames.size() == Piece::NUM_PIECES, "Mismatch between piece names and types");
+    return pieceNames[m_type];
+}
+
+char Piece::initial() const {
+    static_assert(blackShort.size() == Piece::NUM_PIECES, "Mismatch between piece names and types");
+    static_assert(whiteShort.size() == Piece::NUM_PIECES, "Mismatch between piece names and types");
+    return m_color ? blackShort[m_type] : whiteShort[m_type];
+}
+
+void Piece::invalidate() {
+    m_update = true;
+}
+
+
+const char* Piece::coord() const {
+    if (m_pos == INVALID_POS) return "";
+    return positions[m_pos];
+}
+
+bool Piece::canReach(char pos) const {
+    return movePattern(pos) && m_allowed.count(pos);
+}
+
+void Piece::take() {
+    m_pos = INVALID_POS;
+    m_allowed = {};
+}
+
+State::State()
+    : blacks {
+        {Piece::Black, "a7"_P, {"a5"_P, "a6"_P} },
+        {Piece::Black, "b7"_P, {"b5"_P, "b6"_P} },
+        {Piece::Black, "c7"_P, {"c5"_P, "c6"_P} },
+        {Piece::Black, "d7"_P, {"d5"_P, "d6"_P} },
+        {Piece::Black, "e7"_P, {"e5"_P, "e6"_P} },
+        {Piece::Black, "f7"_P, {"f5"_P, "f6"_P} },
+        {Piece::Black, "g7"_P, {"g5"_P, "g6"_P} },
+        {Piece::Black, "h7"_P, {"h5"_P, "h6"_P} },
+        {Piece::Black, "a8"_P},
+        {Piece::Black, "b8"_P, {"a6"_P, "c6"_P} },
+        {Piece::Black, "c8"_P},
+        {Piece::Black, "d8"_P},
+        {Piece::Black, "e8"_P},
+        {Piece::Black, "f8"_P},
+        {Piece::Black, "g8"_P, {"f6"_P, "h6"_P} },
+        {Piece::Black, "h8"_P},
+    }
+    , whites {
+        {Piece::White, "a2"_P, {"a3"_P, "a4"_P} },
+        {Piece::White, "b2"_P, {"b3"_P, "b4"_P} },
+        {Piece::White, "c2"_P, {"c3"_P, "c4"_P} },
+        {Piece::White, "d2"_P, {"d3"_P, "d4"_P} },
+        {Piece::White, "e2"_P, {"e3"_P, "e4"_P} },
+        {Piece::White, "f2"_P, {"f3"_P, "f4"_P} },
+        {Piece::White, "g2"_P, {"g3"_P, "g4"_P} },
+        {Piece::White, "h2"_P, {"h3"_P, "h4"_P} },
+        {Piece::White, "a1"_P},
+        {Piece::White, "b1"_P, {"a3"_P, "c3"_P} },
+        {Piece::White, "c1"_P},
+        {Piece::White, "d1"_P},
+        {Piece::White, "e1"_P},
+        {Piece::White, "f1"_P},
+        {Piece::White, "g1"_P, {"f3"_P, "h3"_P} },
+        {Piece::White, "h1"_P},
+    }
+    , board {{
+        &whites[ 8],  &whites[ 9],  &whites[10],  &whites[11],  &whites[12],  &whites[13],  &whites[14],  &whites[15],
+        &whites[ 0],  &whites[ 1],  &whites[ 2],  &whites[ 3],  &whites[ 4],  &whites[ 5],  &whites[ 6],  &whites[ 7],
+        nullptr,      nullptr,      nullptr,      nullptr,      nullptr,      nullptr,      nullptr,      nullptr,
+        nullptr,      nullptr,      nullptr,      nullptr,      nullptr,      nullptr,      nullptr,      nullptr,
+        nullptr,      nullptr,      nullptr,      nullptr,      nullptr,      nullptr,      nullptr,      nullptr,
+        nullptr,      nullptr,      nullptr,      nullptr,      nullptr,      nullptr,      nullptr,      nullptr,
+        &blacks[ 0],  &blacks[ 1],  &blacks[ 2],  &blacks[ 3],  &blacks[ 4],  &blacks[ 5],  &blacks[ 6],  &blacks[ 7],
+        &blacks[ 8],  &blacks[ 9],  &blacks[10],  &blacks[11],  &blacks[12],  &blacks[13],  &blacks[14],  &blacks[15],
+    }}
+{}
+
+Chessboard::Chessboard()
+    : m_state(new State())
+{
+    setGrammar();
+}
+
+Chessboard::~Chessboard() = default;
+
+void Chessboard::setPrompt(const std::string& prompt) {
+    m_prompt = prompt;
+    setGrammar();
+}
+
+void Chessboard::setGrammar() {
+    m_grammar.clear();
+
+    std::string result;
+    if (m_prompt.empty()) {
+        result += "move ::= \" \" ((piece | frompos) \" \" \"to \"?)? topos\n";
+        //result += "move ::= \" \" frompos \" \" \"to \"? topos\n";
+    }
+    else {
+        // result += "move ::= prompt \" \" ((piece | frompos) \" \" \"to \"?)? topos\n"
+        result += "move ::= prompt \" \" frompos \" \" \"to \"? topos\n"
+        "prompt ::= \" " + m_prompt + "\"\n";
+    }
+
+    std::set<Piece::Types> pieceTypes;
+    std::set<char> from_pos;
+    std::set<char> to_pos;
+    auto& pieces =  m_moveCounter % 2 ? m_state->blacks : m_state->whites;
+    std::set<size_t> flags;
+    for (auto& p : pieces) {
+        if (p.allowed().empty()) continue;
+        bool addPiece = false;
+        if (!m_inCheck || p.type() == Piece::King) {
+            to_pos.insert(p.allowed().begin(), p.allowed().end());
+            addPiece = !p.allowed().empty();
+        }
+        else {
+            for (auto move : p.allowed()) {
+                if (m_allowedInCheck.count(move)) {
+                    to_pos.insert(move);
+                    addPiece = true;
+                }
+            }
+        }
+        if (addPiece) {
+            pieceTypes.insert(p.type());
+            from_pos.insert(p.pos());
+        }
+    }
+    if (pieceTypes.empty()) return;
+
+    result += "piece ::= (";
+    for (auto& p : pieceTypes) result += " \"" + std::string(pieceNames[p]) + "\" |";
+    result.pop_back();
+    result += ")\n\n";
+
+    result += "frompos ::= (";
+    for (auto& p : from_pos) result += " \"" + std::string(positions[p]) + "\" |";
+    result.pop_back();
+    result += ")\n";
+
+    result += "topos ::= (";
+    for (auto& p : to_pos) result += " \"" + std::string(positions[p]) + "\" |";
+    result.pop_back();
+    result += ")\n";
+
+    m_grammar = std::move(result);
+}
+
+std::string Chessboard::stringifyBoard() {
+    std::string result;
+    result.reserve(16 + 2 * 64 + 16);
+    for (char rank = 'a'; rank <= 'h'; ++rank) {
+        result.push_back(rank);
+        result.push_back(' ');
+    }
+    result.back() = '\n';
+    for (int i = 7; i >= 0; --i) {
+        for (int j = 0; j < 8; ++j) {
+            auto p = m_state->board[i * 8 + j];
+            if (p) result.push_back(p->initial());
+            else result.push_back((i + j) % 2 ? '.' : '*');
+            result.push_back(' ');
+        }
+        result.push_back('0' + i + 1);
+        result.push_back('\n');
+    }
+    return result;
+}
+
+std::string Chessboard::process(const std::string& command) {
+    const auto t_start = std::chrono::high_resolution_clock::now();
+    auto color = Piece::Colors(m_moveCounter % 2);
+    Piece* piece = nullptr;
+    auto pos_to = INVALID_POS;
+    if (!parseCommand(command, piece, pos_to)) return "";
+
+    auto pos_from = piece->pos();
+
+    if (!move(*piece, pos_to)) return "";
+
+    flagUpdates(pos_from, pos_to);
+
+    detectChecks();
+
+    auto& enemyPieces = color ? m_state->whites : m_state->blacks;
+    for (auto& p : enemyPieces) p.reinit(*m_state); // only enemy moves needed next
+
+    std::string result = {positions[pos_from][R], positions[pos_from][F], '-', positions[pos_to][R], positions[pos_to][F]};
+    ++m_moveCounter;
+    setGrammar();
+    const auto t_end = std::chrono::high_resolution_clock::now();
+    auto t_ms = std::chrono::duration_cast<std::chrono::milliseconds>(t_end - t_start).count();
+    fprintf(stdout, "%s: Move '%s%s%s', (t = %d ms)\n", __func__, "\033[1m", result.data(), "\033[0m", (int) t_ms);
+    if (m_grammar.empty()) result.push_back('#');
+    return result;
+}
+
+bool Chessboard::parseCommand(const std::string& command, Piece*& piece, char& pos_to) {
+    auto color = Piece::Colors(m_moveCounter % 2);
+    fprintf(stdout, "%s: Command to %s: '%s%.*s%s'\n", __func__, (color ? "Black" : "White"), "\033[1m", int(command.size()), command.data(), "\033[0m");
+
+    if (command.empty()) return false;
+    auto tokens = split(command, ' ');
+    auto pos_from = INVALID_POS;
+    auto type = Piece::Types::NUM_PIECES;
+    if (tokens.size() == 1) {
+        type = Piece::Types::Pawn;
+        pos_to = strToPos(tokens.front());
+    }
+    else {
+        pos_from = strToPos(tokens.front());
+        if (pos_from == INVALID_POS) type = Piece::Types(strToType(tokens.front()));
+        pos_to = strToPos(tokens.back());
+    }
+    if (pos_to == INVALID_POS) return false;
+    if (pos_from == INVALID_POS) {
+        if (type == Piece::Types::NUM_PIECES) return false;
+        auto& pieces = color ? m_state->blacks : m_state->whites;
+        for (auto& p : pieces) {
+            if (p.type() == type && p.canReach(pos_to)) {
+                pos_from = p.pos();
+                break;
+            }
+        }
+    }
+    if (pos_from == INVALID_POS) return false;
+    if (m_state->board[pos_from] == nullptr) return false;
+    piece = m_state->board[pos_from];
+    if (piece->color() != color) return false;
+    return true;
+}
+
+void Chessboard::flagUpdates(char pos_from, char pos_to) {
+    auto color = Piece::Colors(m_moveCounter % 2);
+    auto& enemyPieces = color ? m_state->whites : m_state->blacks;
+    auto& ownPieces = color ? m_state->blacks : m_state->whites;
+    for (auto& p : enemyPieces) {
+        if (p.movePattern(pos_to) || p.movePattern(pos_from)) {
+            updatePins(p);
+            p.invalidate();
+        }
+    }
+
+    for (auto& p : ownPieces) {
+        if (p.movePattern(pos_to) || p.movePattern(pos_from)) {
+            updatePins(p);
+            p.invalidate();
+        }
+    }
+}
+
+void Chessboard::updatePins(Piece& piece) {
+    if (piece.type() == Piece::Pawn || piece.type() == Piece::Knight || piece.type() == Piece::King) return;
+    auto& enemyPieces = piece.color() ? m_state->whites : m_state->blacks;
+    auto& enemyPins = piece.color() ? m_state->whitePins : m_state->blackPins;
+    auto& king = enemyPieces.k;
+    auto it = std::find_if(enemyPins.begin(), enemyPins.end(), [&] (const Pin& pin) { return pin.pinner == &piece; });
+    if (it != enemyPins.end()) {
+        it->pinned->invalidate();
+        enemyPins.erase(it);
+    }
+    if (piece.movePattern(king.pos())) {
+        auto to = positions[king.pos()];
+        auto from = piece.coord();
+        Direction d = normalize({char(to[R] - from[R]), char(to[F] - from[F])});
+
+        auto reached = traverse(piece.pos(), d, Find(m_state->board));
+        auto foundPiece = m_state->board[reached];
+        if (&king == foundPiece) {
+            // check
+            king.invalidate();
+        }
+        else if (foundPiece && foundPiece->color() != piece.color()) {
+            reached = traverse(reached, d, Find(m_state->board));
+            if (&king == m_state->board[reached]) {
+                enemyPins.push_back({d, &piece, foundPiece});
+                foundPiece->invalidate();
+            }
+        }
+    }
+}
+
+void Chessboard::detectChecks() {
+    auto color = Piece::Colors(m_moveCounter % 2);
+    auto& enemyPieces = color ? m_state->whites : m_state->blacks;
+    auto& ownPieces = color ? m_state->blacks : m_state->whites;
+    auto& king = enemyPieces.k;
+    auto& pawnAttackLeft = color ? SW : NW;
+    auto& pawnAttackRight = color ? SE : NE;
+    for (auto& p : ownPieces) {
+        if (!p.movePattern(king.pos())) continue;
+        auto to = positions[king.pos()];
+        auto from = p.coord();
+
+        if (p.type() == Piece::Knight) {
+            if (!m_inCheck) {
+                m_allowedInCheck = { p.pos() };
+            }
+            else {
+                m_allowedInCheck.clear();
+            }
+            m_inCheck = true;
+        }
+        else if (p.type() == Piece::Pawn) {
+            Direction d {char(to[R] - from[R]), char(to[F] - from[F])};
+            if (d == pawnAttackLeft || d == pawnAttackRight) {
+                if (!m_inCheck) {
+                    m_allowedInCheck = { p.pos() };
+                }
+                else {
+                    m_allowedInCheck.clear();
+                }
+                m_inCheck = true;
+            }
+        }
+        else {
+            Direction d = normalize({char(to[R] - from[R]), char(to[F] - from[F])});
+            std::set<char> tmp;
+            auto pos = traverse(p.pos(), d, Add(m_state->board, tmp, king.color()));
+            if (pos == king.pos()) {
+                tmp.insert(p.pos());
+                if (!m_inCheck) {
+                    m_allowedInCheck = std::move(tmp);
+                }
+                else {
+                    m_allowedInCheck.clear();
+                }
+                m_inCheck = true;
+            }
+        }
+    }
+}
+
+bool Chessboard::move(Piece& piece, char pos_to) {
+    auto& allowed = piece.allowed();
+
+    if (allowed.count(pos_to) == 0 || (m_inCheck && piece.type() != Piece::King && m_allowedInCheck.count(pos_to) == 0)) return false;
+    if (m_state->board[pos_to] && m_state->board[pos_to]->color() == piece.color()) return false;
+    if (m_state->board[pos_to]) m_state->board[pos_to]->take();
+    m_state->board[piece.pos()] = nullptr;
+    m_state->board[pos_to] = &piece;
+    piece.setPos(pos_to);
+
+    m_inCheck = false;
+    m_allowedInCheck.clear();
+
+    return true;
+}

whisper.cpp-1.5.2/examples/wchess/libwchess/Chessboard.h

@@ -0,0 +1,33 @@
+#pragma once
+#include <string>
+#include <set>
+#include <memory>
+
+// just basic validation
+// fixme: missing en passant, castling, promotion, etc.
+struct State;
+class Piece;
+class Chessboard {
+public:
+    Chessboard();
+    ~Chessboard();
+    std::string process(const std::string& command);
+    std::string stringifyBoard();
+    const std::string& grammar() { return m_grammar; }
+    const std::string& prompt() { return m_prompt; }
+    void setPrompt(const std::string& prompt);
+private:
+    bool parseCommand(const std::string& command, Piece*& piece, char& pos_to);
+    bool move(Piece& piece, char pos);
+    void flagUpdates(char pos_from, char pos_to);
+    void updatePins(Piece& piece);
+    void detectChecks();
+    void setGrammar();
+
+    std::unique_ptr<State> m_state;
+    std::set<char> m_allowedInCheck;
+    bool m_inCheck = false;
+    int m_moveCounter = 0;
+    std::string m_grammar;
+    std::string m_prompt;
+};

whisper.cpp-1.5.2/examples/wchess/libwchess/WChess.cpp

@@ -0,0 +1,193 @@
+#include "WChess.h"
+#include "Chessboard.h"
+#include "grammar-parser.h"
+#include "common.h"
+#include <thread>
+
+WChess::WChess(whisper_context * ctx,
+        const whisper_full_params & wparams,
+        callbacks cb,
+        settings s)
+        : m_ctx(ctx)
+        , m_wparams(wparams)
+        , m_cb(cb)
+        , m_settings(s)
+        , m_board(new Chessboard())
+{}
+
+WChess::~WChess() = default;
+
+void WChess::set_move(const std::string& moves, float prob) const {
+    if (m_cb.set_move) (*m_cb.set_move)(moves, prob);
+}
+
+void WChess::set_grammar(const std::string& grammar) const {
+    if (m_cb.set_grammar) (*m_cb.set_grammar)(grammar);
+}
+
+bool WChess::get_audio(std::vector<float>& pcmf32) const {
+    if (m_cb.get_audio) return (*m_cb.get_audio)(pcmf32);
+    return false;
+}
+
+std::string WChess::stringify_board() const {
+    return m_board->stringifyBoard();
+}
+
+std::string WChess::get_grammar() const {
+    return m_board->grammar();
+}
+
+void WChess::run() {
+    bool have_prompt  = true;
+    bool ask_prompt   = !have_prompt;
+
+    float logprob_min  = 0.0f;
+
+    float logprob_sum  = 0.0f;
+
+    int n_tokens  = 0;
+
+    std::vector<float> pcmf32_cur;
+    std::vector<float> pcmf32_prompt;
+
+    const std::string k_prompt = have_prompt ? "" : "rook to d4, f3";
+    int64_t t_ms = 0;
+
+    if (ask_prompt) {
+        fprintf(stdout, "\n");
+        fprintf(stdout, "%s: Say the following phrase: '%s%s%s'\n", __func__, "\033[1m", k_prompt.c_str(), "\033[0m");
+        fprintf(stdout, "\n");
+
+        ask_prompt = false;
+    }
+
+    while (get_audio(pcmf32_cur)) {
+        if (!pcmf32_cur.empty()) {
+            // fprintf(stdout, "%s: Processing ...\n", __func__);
+
+            if (!have_prompt) {
+                const auto txt = ::trim(transcribe(pcmf32_cur, logprob_min, logprob_sum, n_tokens, t_ms));
+
+                fprintf(stdout, "%s: Heard '%s%s%s', (t = %d ms)\n", __func__, "\033[1m", txt.c_str(), "\033[0m", (int) t_ms);
+
+                const float sim = similarity(txt, k_prompt);
+
+                if (txt.length() < 0.8*k_prompt.length() || txt.length() > 1.2*k_prompt.length() || sim < 0.8f) {
+                    fprintf(stdout, "%s: WARNING: prompt not recognized, try again\n", __func__);
+                    ask_prompt = true;
+                } else {
+                    fprintf(stdout, "\n");
+                    fprintf(stdout, "%s: The prompt has been recognized!\n", __func__);
+                    fprintf(stdout, "%s: Waiting for voice commands ...\n", __func__);
+                    fprintf(stdout, "\n");
+
+                    // save the audio for the prompt
+                    pcmf32_prompt = pcmf32_cur;
+                    have_prompt = true;
+                    m_board->setPrompt(k_prompt);
+                }
+            } else {
+                if (!pcmf32_prompt.empty()) pcmf32_cur.insert(pcmf32_cur.begin(), pcmf32_prompt.begin(), pcmf32_prompt.end());
+                constexpr size_t MIN_SIZE = 1.2 * WHISPER_SAMPLE_RATE;
+                if (MIN_SIZE > pcmf32_cur.size()) pcmf32_cur.insert(pcmf32_cur.begin(), MIN_SIZE - pcmf32_cur.size(), 0.0f);
+
+                // fprintf(stdout, "%s: grammar rules:\n'%s'\n", __func__, m_board->grammar().c_str());
+
+                auto grammar_parsed = grammar_parser::parse(m_board->grammar().c_str());
+                auto grammar_rules  = grammar_parsed.c_rules();
+
+                m_wparams.grammar_rules   = grammar_rules.data();
+                m_wparams.n_grammar_rules = grammar_rules.size();
+
+                m_wparams.i_start_rule    = grammar_parsed.symbol_ids.at("move");
+                auto txt = ::trim(transcribe(pcmf32_cur, logprob_min, logprob_sum, n_tokens, t_ms));
+
+                const float p = 100.0f * std::exp(logprob_min);
+
+                fprintf(stdout, "%s: heard '%s'\n", __func__, txt.c_str());
+
+                // find the prompt in the text
+                float best_sim = 0.0f;
+                size_t best_len = 0;
+                for (int n = 0.8*k_prompt.size(); n <= 1.2*k_prompt.size(); ++n) {
+                    const auto prompt = txt.substr(0, n);
+
+                    const float sim = similarity(prompt, k_prompt);
+
+                    //fprintf(stderr, "%s: prompt = '%s', sim = %f\n", __func__, prompt.c_str(), sim);
+
+                    if (sim > best_sim) {
+                        best_sim = sim;
+                        best_len = n;
+                    }
+                }
+
+                fprintf(stdout, "%s:   DEBUG: txt = '%s', prob = %.2f%%\n", __func__, txt.c_str(), p);
+                std::string command = ::trim(txt.substr(best_len));
+
+                fprintf(stdout, "%s: Command '%s%s%s', (t = %d ms)\n", __func__, "\033[1m", command.c_str(), "\033[0m", (int) t_ms);
+                fprintf(stdout, "\n");
+
+                if (!command.empty()) {
+                    set_move(m_board->process(command), p);
+                    set_grammar(m_board->grammar());
+                }
+                if (m_board->grammar().empty()) {
+                    fprintf(stdout, "%s: No more moves possible\n", __func__);
+                    break;
+                }
+            }
+        }
+
+        if (ask_prompt) {
+            fprintf(stdout, "\n");
+            fprintf(stdout, "%s: Say the following phrase: '%s%s%s'\n", __func__, "\033[1m", k_prompt.c_str(), "\033[0m");
+            fprintf(stdout, "\n");
+
+            ask_prompt = false;
+        }
+    }
+}
+
+std::string WChess::transcribe(
+                const std::vector<float> & pcmf32,
+                float & logprob_min,
+                float & logprob_sum,
+                int & n_tokens,
+                int64_t & t_ms) {
+    const auto t_start = std::chrono::high_resolution_clock::now();
+
+    logprob_min = 0.0f;
+    logprob_sum = 0.0f;
+    n_tokens    = 0;
+    t_ms = 0;
+
+    if (whisper_full(m_ctx, m_wparams, pcmf32.data(), pcmf32.size()) != 0) {
+        return {};
+    }
+
+    std::string result;
+
+    const int n_segments = whisper_full_n_segments(m_ctx);
+    for (int i = 0; i < n_segments; ++i) {
+        const char * text = whisper_full_get_segment_text(m_ctx, i);
+
+        result += text;
+
+        const int n = whisper_full_n_tokens(m_ctx, i);
+        for (int j = 0; j < n; ++j) {
+            const auto token = whisper_full_get_token_data(m_ctx, i, j);
+
+            if(token.plog > 0.0f) return {};
+            logprob_min = std::min(logprob_min, token.plog);
+            logprob_sum += token.plog;
+            ++n_tokens;
+        }
+    }
+
+    const auto t_end = std::chrono::high_resolution_clock::now();
+    t_ms = std::chrono::duration_cast<std::chrono::milliseconds>(t_end - t_start).count();
+
+    return result;
+}

whisper.cpp-1.5.2/examples/wchess/libwchess/WChess.h

@@ -0,0 +1,63 @@
+#pragma once
+#include "whisper.h"
+#include <string>
+#include <vector>
+#include <memory>
+
+class Chessboard;
+
+class WChess {
+public:
+    using CheckRunningCb = bool (*)();
+    using GetAudioCb = bool (*)(std::vector<float> &);
+    using SetMovesCb = void (*)(const std::string &, float);
+    using SetGrammarCb = void (*)(const std::string &);
+    using ClearAudioCb = void (*)();
+
+    struct callbacks {
+        GetAudioCb get_audio = nullptr;
+        SetMovesCb set_move = nullptr;
+        SetGrammarCb set_grammar = nullptr;
+    };
+
+    struct settings {
+        int32_t vad_ms     = 2000;
+        int32_t prompt_ms  = 5000;
+        int32_t command_ms = 4000;
+        float vad_thold    = 0.2f;
+        float freq_thold   = 100.0f;
+        bool print_energy  = false;
+    };
+
+    WChess(
+        whisper_context * ctx,
+        const whisper_full_params & wparams,
+        callbacks cb,
+        settings s
+    );
+    ~WChess();
+
+    void run();
+
+    std::string stringify_board() const;
+
+    std::string get_grammar() const;
+
+private:
+    bool get_audio(std::vector<float>& pcmf32) const;
+    void set_move(const std::string& moves, float prob) const;
+    void set_grammar(const std::string& grammar) const;
+
+    std::string transcribe(
+                    const std::vector<float> & pcmf32,
+                    float & logprob_min,
+                    float & logprob_sum,
+                    int & n_tokens,
+                    int64_t & t_ms);
+
+    whisper_context * m_ctx;
+    whisper_full_params m_wparams;
+    const callbacks m_cb;
+    const settings m_settings;
+    std::unique_ptr<Chessboard> m_board;
+};

whisper.cpp-1.5.2/examples/wchess/libwchess/test-chessboard.cpp

@@ -0,0 +1,117 @@
+#include "Chessboard.h"
+
+#define ASSERT(x) \
+    do { \
+        if (!(x)) { \
+            fprintf(stderr, "ASSERT: %s:%d: %s\n", __FILE__, __LINE__, #x); \
+            fflush(stderr); \
+            exit(1); \
+        } \
+    } while (0)
+
+
+int main() {
+    {
+        Chessboard chess;
+
+        ASSERT(chess.process("pawn to d4") == "d2-d4");
+        ASSERT(chess.process("e5") == "e7-e5");
+        ASSERT(chess.process("c1 h6") == "c1-h6");
+        ASSERT(chess.process("queen h4") == "d8-h4");
+        ASSERT(chess.process("bishop to g5") == "h6-g5");
+        ASSERT(chess.process("bishop to b4") == "f8-b4");
+        ASSERT(chess.process("c4") == "");
+        ASSERT(chess.process("knight c3") == "b1-c3");
+        ASSERT(chess.process("knight c6") == "b8-c6");
+        ASSERT(chess.process("f3") == "");
+    }
+
+    {
+        Chessboard chess;
+
+        ASSERT(chess.process("d4") == "d2-d4");
+        ASSERT(chess.process("e5") == "e7-e5");
+        ASSERT(chess.process("e4") == "e2-e4");
+        ASSERT(chess.process("queen h4") == "d8-h4");
+        ASSERT(chess.process("queen h5") == "d1-h5");
+        ASSERT(chess.process("f5") == "");
+        ASSERT(chess.process("g6") == "g7-g6");
+        ASSERT(chess.process("knight e2") == "g1-e2");
+        ASSERT(chess.process("f5") == "f7-f5");
+        ASSERT(chess.process("knight g3") == "e2-g3");
+        ASSERT(chess.process("g5") == "");
+        ASSERT(chess.process("king e7") == "e8-e7");
+        ASSERT(chess.process("f4") == "f2-f4");
+        ASSERT(chess.process("g5") == "g6-g5");
+    }
+
+    {
+        Chessboard chess;
+
+        ASSERT(chess.process("e4") == "e2-e4");
+        ASSERT(chess.process("c5") == "c7-c5");
+        ASSERT(chess.process("e5") == "e4-e5");
+        ASSERT(chess.process("c4") == "c5-c4");
+        ASSERT(chess.process("e6") == "e5-e6");
+        ASSERT(chess.process("c3") == "c4-c3");
+        ASSERT(chess.process("e7") == "");
+        ASSERT(chess.process("f7") == "e6-f7");
+        ASSERT(chess.process("d2") == "");
+        ASSERT(chess.process("king to f7") == "e8-f7");
+        ASSERT(chess.process("f4") == "f2-f4");
+        ASSERT(chess.process("d2") == "c3-d2");
+        ASSERT(chess.process("f5") == "");
+        ASSERT(chess.process("king to e2") == "e1-e2");
+        ASSERT(chess.process("king to g6") == "f7-g6");
+        ASSERT(chess.process("f5") == "f4-f5");
+        ASSERT(chess.process("e6") == "");
+        ASSERT(chess.process("king to h5") == "g6-h5");
+        ASSERT(chess.process("g4") == "g2-g4");
+        ASSERT(chess.process("king to g5") == "h5-g5");
+        ASSERT(chess.process("h4") == "h2-h4");
+        ASSERT(chess.process("king to h5") == "");
+        ASSERT(chess.process("king to g6") == "");
+        ASSERT(chess.process("king to h6") == "g5-h6");
+        ASSERT(chess.process("bishop to d2") == "c1-d2");
+        ASSERT(chess.process("king to g5") == "");
+        ASSERT(chess.process("g5") == "g7-g5");
+    }
+
+    {
+        Chessboard chess;
+        ASSERT(chess.process("f4") == "f2-f4");
+        ASSERT(chess.process("e5") == "e7-e5");
+        ASSERT(chess.process("g4") == "g2-g4");
+        ASSERT(chess.process("queen to h4") == "d8-h4#");
+        ASSERT(chess.process("knight f3") == "");
+        ASSERT(chess.grammar().empty());
+    }
+
+    {
+        Chessboard chess;
+        ASSERT(chess.process("f4") == "f2-f4");
+        ASSERT(chess.process("e5") == "e7-e5");
+        ASSERT(chess.process("g4") == "g2-g4");
+        ASSERT(chess.process("d5") == "d7-d5");
+        ASSERT(chess.process("g1 f3") == "g1-f3");
+        ASSERT(chess.process("queen to h4") == "d8-h4");
+        ASSERT(!chess.grammar().empty());
+    }
+
+    {
+        Chessboard chess;
+        ASSERT(chess.process("knight c3") == "b1-c3");
+        ASSERT(chess.process("knight c6") == "b8-c6");
+        ASSERT(chess.process("knight b5") == "c3-b5");
+        ASSERT(chess.process("knight f6") == "g8-f6");
+        ASSERT(chess.process("knight d6") == "b5-d6");
+        ASSERT(chess.process("knight d4") == "");
+        ASSERT(chess.process("d6") == "c7-d6");
+        ASSERT(chess.process("e4") == "e2-e4");
+        ASSERT(chess.process("knight d4") == "c6-d4");
+        ASSERT(chess.process("d3") == "d2-d3");
+        ASSERT(chess.process("knight e4") == "f6-e4");
+        ASSERT(chess.process("king to e2") == "");
+        ASSERT(chess.process("king to d2") == "");
+    }
+}